Remove obsolete styles for bullets

The toggle is now a link element, so we can let the skin choose its
color.

cursor and text-decoration had no effect because the triangle is
rendered by borders and the element itself is empty.

speak is deprecated, and since the toggle is reachable by keyboard now,
it's no longer appropriate.

Change-Id: Id522b78d185d951b0739758ad20bb5b3dbbc546e

modules/ext.categoryTree.styles.css

@@ -78,7 +78,6 @@
 
 .CategoryTreeBullet,
 .CategoryTreeEmptyBullet {
-	cursor: default;
 	-webkit-user-select: none;
 	-moz-user-select: none;
 	-ms-user-select: none;
@@ -89,25 +88,12 @@
 	color: #c0c0c0;
 }
 
-.CategoryTreeBullet a,
-.CategoryTreeBullet a:link,
-.CategoryTreeBullet a:active,
-.CategoryTreeBullet a:visited {
-	text-decoration: none;
-	color: inherit;
-	speak: none;
-}
-
 /* Hide toggle buttons for clients without JavaScript */
 .client-nojs .CategoryTreeBullet,
 .client-nojs .CategoryTreeEmptyBullet {
 	display: none;
 }
 
-.CategoryTreeToggle {
-	color: #0645ad;
-}
-
 .CategoryTreeEmptyBullet,
 .CategoryTreeToggle,
 .CategoryTreePageBullet {